(19)

(11)

EP 0 938 634 A2

(12)

(43) Date of publication: 01.09.1999 Bulletin 1999/35 (21) Application number: 97913896.0 (22) Date of filing: 29.10.1997

(51) International Patent Classification (IPC):  F16K 27/ 00( . ) C23C 16/ 455( . ) F16K 51/ 00( . ) H01L 21/ 00( . ) C23C 16/ 44( . ) F16K 11/ 10( . ) H01J 37/ 32( . ) H01L 21/ 304( . ) (86) International application number: PCT/US1997/019709 (87) International publication number: WO 1998/021744 (22.05.1998 Gazette 1998/20)

(84) Designated Contracting States: DE FR GB IE IT (30) Priority: 30.10.1996 US 19960739936 (71) Applicant: UNIT INSTRUMENTS, INC. Yorba Linda, CA 92687 (US)	(72) Inventors: REDEMANN, Eric, J. Laguna Niguel, CA 92677 (US) VU, Kim, N. Yorba Linda, CA 92886 (US) (74) Representative: HOFFMANN - EITLE  Patent- und Rechtsanwälte Arabellastrasse 4 81925 München 81925 München (DE)